#ifndef system_h
    #define system_h
     //IO 口地址映射
    #define GPIOA_IDR_Addr (GPIOA_BASE+8) //0x40010808
    #define GPIOB_IDR_Addr (GPIOB_BASE+8) //0x40010C08
    #define GPIOC_IDR_Addr (GPIOC_BASE+8) //0x40011008
    #define GPIOD_IDR_Addr (GPIOD_BASE+8) //0x40011408
    #define GPIOE_IDR_Addr (GPIOE_BASE+8) //0x40011808
    #define GPIOF_IDR_Addr (GPIOF_BASE+8) //0x40011A08
    #define GPIOG_IDR_Addr (GPIOG_BASE+8) //0x40011E08
    #define GPIOA_ODR_Addr (GPIOA_BASE+12) //0x4001080C
    #define GPIOB_ODR_Addr (GPIOB_BASE+12) //0x40010C0C
    #define GPIOC_ODR_Addr (GPIOC_BASE+12) //0x4001100C
    #define GPIOD_ODR_Addr (GPIOD_BASE+12) //0x4001140C
    #define GPIOE_ODR_Addr (GPIOE_BASE+12) //0x4001180C
    #define GPIOF_ODR_Addr (GPIOF_BASE+12) //0x40011A0C
    #define GPIOG_ODR_Addr (GPIOG_BASE+12) //0x40011E0C

    #define BITBAND(addr, bitnum) ((addr & 0xF0000000)+0x2000000+((addr&0xFFFFF)<<5)+(bitnum<<2))
    //把 addr 地址强制转换为 unsigned long 类型的指针
    #define MEM_ADDR(addr) *((volatile unsigned long *)(addr))
    //把位带别名区内地址转换为指针 ，获取地址内的数据
    #define BIT_ADDR(addr, bitnum) MEM_ADDR(BITBAND(addr, bitnum))
    //IO 口操作,只对单一的 IO 口!
    //确保 n 的值小于 16!
    #define PAin(n) 	BIT_ADDR(GPIOA_IDR_Addr,n) //输入
    #define PBin(n) 	BIT_ADDR(GPIOB_IDR_Addr,n) //输入
    #define PCin(n) 	BIT_ADDR(GPIOC_IDR_Addr,n) //输入
    #define PDin(n) 	BIT_ADDR(GPIOD_IDR_Addr,n) //输入
    #define PEin(n) 	BIT_ADDR(GPIOE_IDR_Addr,n) //输入
    #define PFin(n) 	BIT_ADDR(GPIOF_IDR_Addr,n) //输入
    #define PGin(n) 	BIT_ADDR(GPIOG_IDR_Addr,n) //输入
    #define PAout(n) 	BIT_ADDR(GPIOA_ODR_Addr,n) //输出
    #define PBout(n) 	BIT_ADDR(GPIOB_ODR_Addr,n) //输出
    #define PCout(n) 	BIT_ADDR(GPIOC_ODR_Addr,n) //输出
    #define PDout(n) 	BIT_ADDR(GPIOD_ODR_Addr,n) //输出
    #define PEout(n) 	BIT_ADDR(GPIOE_ODR_Addr,n) //输出
    #define PFout(n) 	BIT_ADDR(GPIOF_ODR_Addr,n) //输出
    #define PGout(n) 	BIT_ADDR(GPIOG_ODR_Addr,n) //输出

#endif
    
    
    
